xref: /freebsd/usr.sbin/pw/pw_group.c (revision 5f0216bd883edee71bf81051e3c20505e4820903)
1 /*-
2  * Copyright (C) 1996
3  *	David L. Nugent.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY DAVID L. NUGENT AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL DAVID L. NUGENT OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #ifndef lint
28 static const char rcsid[] =
29   "$FreeBSD$";
30 #endif /* not lint */
31 
32 #include <ctype.h>
33 #include <err.h>
34 #include <termios.h>
35 #include <stdbool.h>
36 #include <unistd.h>
37 #include <grp.h>
38 #include <libutil.h>
39 
40 #include "pw.h"
41 #include "bitmap.h"
42 
43 
44 static struct passwd *lookup_pwent(const char *user);
45 static void	delete_members(char ***members, int *grmembers, int *i,
46     struct carg *arg, struct group *grp);
47 static int	print_group(struct group * grp);
48 static gid_t    gr_gidpolicy(struct userconf * cnf, long id);
49 
50 int
51 pw_group(int mode, char *name, long id, struct cargs * args)
52 {
53 	int		rc;
54 	struct carg    *arg;
55 	struct group   *grp = NULL;
56 	int	        grmembers = 0;
57 	char           **members = NULL;
58 	struct userconf	*cnf = conf.userconf;
59 
60 	static struct group fakegroup =
61 	{
62 		"nogroup",
63 		"*",
64 		-1,
65 		NULL
66 	};
67 
68 	if (mode == M_LOCK || mode == M_UNLOCK)
69 		errx(EX_USAGE, "'lock' command is not available for groups");
70 
71 	/*
72 	 * With M_NEXT, we only need to return the
73 	 * next gid to stdout
74 	 */
75 	if (mode == M_NEXT) {
76 		gid_t next = gr_gidpolicy(cnf, id);
77 		if (getarg(args, 'q'))
78 			return next;
79 		printf("%u\n", next);
80 		return EXIT_SUCCESS;
81 	}
82 
83 	if (mode == M_PRINT && getarg(args, 'a')) {
84 		SETGRENT();
85 		while ((grp = GETGRENT()) != NULL)
86 			print_group(grp);
87 		ENDGRENT();
88 		return EXIT_SUCCESS;
89 	}
90 	if (id < 0 && name == NULL)
91 		errx(EX_DATAERR, "group name or id required");
92 
93 	grp = (name != NULL) ? GETGRNAM(name) : GETGRGID(id);
94 
95 	if (mode == M_UPDATE || mode == M_DELETE || mode == M_PRINT) {
96 		if (name == NULL && grp == NULL)	/* Try harder */
97 			grp = GETGRGID(id);
98 
99 		if (grp == NULL) {
100 			if (mode == M_PRINT && getarg(args, 'F')) {
101 				char	*fmems[1];
102 				fmems[0] = NULL;
103 				fakegroup.gr_name = name ? name : "nogroup";
104 				fakegroup.gr_gid = (gid_t) id;
105 				fakegroup.gr_mem = fmems;
106 				return print_group(&fakegroup);
107 			}
108 			if (name == NULL)
109 				errx(EX_DATAERR, "unknown group `%s'", name);
110 			else
111 				errx(EX_DATAERR, "unknown group `%ld'", id);
112 		}
113 		if (name == NULL)	/* Needed later */
114 			name = grp->gr_name;
115 
116 		/*
117 		 * Handle deletions now
118 		 */
119 		if (mode == M_DELETE) {
120 			rc = delgrent(grp);
121 			if (rc == -1)
122 				err(EX_IOERR, "group '%s' not available (NIS?)",
123 				    name);
124 			else if (rc != 0) {
125 				err(EX_IOERR, "group update");
126 			}
127 			pw_log(cnf, mode, W_GROUP, "%s(%ld) removed", name, id);
128 			return EXIT_SUCCESS;
129 		} else if (mode == M_PRINT)
130 			return print_group(grp);
131 
132 		if (id > 0)
133 			grp->gr_gid = (gid_t) id;
134 
135 		if (conf.newname != NULL)
136 			grp->gr_name = pw_checkname(conf.newname, 0);
137 	} else {
138 		if (name == NULL)	/* Required */
139 			errx(EX_DATAERR, "group name required");
140 		else if (grp != NULL)	/* Exists */
141 			errx(EX_DATAERR, "group name `%s' already exists", name);
142 
143 		extendarray(&members, &grmembers, 200);
144 		members[0] = NULL;
145 		grp = &fakegroup;
146 		grp->gr_name = pw_checkname(name, 0);
147 		grp->gr_passwd = "*";
148 		grp->gr_gid = gr_gidpolicy(cnf, id);
149 		grp->gr_mem = members;
150 	}
151 
152 	/*
153 	 * This allows us to set a group password Group passwords is an
154 	 * antique idea, rarely used and insecure (no secure database) Should
155 	 * be discouraged, but it is apparently still supported by some
156 	 * software.
157 	 */
158 
159 	if ((arg = getarg(args, 'h')) != NULL ||
160 	    (arg = getarg(args, 'H')) != NULL) {
161 		if (strcmp(arg->val, "-") == 0)
162 			grp->gr_passwd = "*";	/* No access */
163 		else {
164 			int             fd = atoi(arg->val);
165 			int		precrypt = (arg->ch == 'H');
166 			int             b;
167 			int             istty = isatty(fd);
168 			struct termios  t;
169 			char           *p, line[256];
170 
171 			if (istty) {
172 				if (tcgetattr(fd, &t) == -1)
173 					istty = 0;
174 				else {
175 					struct termios  n = t;
176 
177 					/* Disable echo */
178 					n.c_lflag &= ~(ECHO);
179 					tcsetattr(fd, TCSANOW, &n);
180 					printf("%sassword for group %s:", (mode == M_UPDATE) ? "New p" : "P", grp->gr_name);
181 					fflush(stdout);
182 				}
183 			}
184 			b = read(fd, line, sizeof(line) - 1);
185 			if (istty) {	/* Restore state */
186 				tcsetattr(fd, TCSANOW, &t);
187 				fputc('\n', stdout);
188 				fflush(stdout);
189 			}
190 			if (b < 0)
191 				err(EX_OSERR, "-h file descriptor");
192 			line[b] = '\0';
193 			if ((p = strpbrk(line, " \t\r\n")) != NULL)
194 				*p = '\0';
195 			if (!*line)
196 				errx(EX_DATAERR, "empty password read on file descriptor %d", fd);
197 			if (precrypt) {
198 				if (strchr(line, ':') != NULL)
199 					return EX_DATAERR;
200 				grp->gr_passwd = line;
201 			} else
202 				grp->gr_passwd = pw_pwcrypt(line);
203 		}
204 	}
205 
206 	if (((arg = getarg(args, 'M')) != NULL ||
207 	    (arg = getarg(args, 'd')) != NULL ||
208 	    (arg = getarg(args, 'm')) != NULL) && arg->val) {
209 		int	i = 0;
210 		char   *p;
211 		struct passwd	*pwd;
212 
213 		/* Make sure this is not stay NULL with -M "" */
214 		extendarray(&members, &grmembers, 200);
215 		if (arg->ch == 'd')
216 			delete_members(&members, &grmembers, &i, arg, grp);
217 		else if (arg->ch == 'm') {
218 			int	k = 0;
219 
220 			if (grp->gr_mem != NULL) {
221 				while (grp->gr_mem[k] != NULL) {
222 					if (extendarray(&members, &grmembers, i + 2) != -1)
223 						members[i++] = grp->gr_mem[k];
224 					k++;
225 				}
226 			}
227 		}
228 
229 		if (arg->ch != 'd')
230 			for (p = strtok(arg->val, ", \t"); p != NULL; p = strtok(NULL, ", \t")) {
231 				int	j;
232 
233 				/*
234 				 * Check for duplicates
235 				 */
236 				pwd = lookup_pwent(p);
237 				for (j = 0; j < i && strcmp(members[j], pwd->pw_name) != 0; j++)
238 					;
239 				if (j == i && extendarray(&members, &grmembers, i + 2) != -1)
240 					members[i++] = newstr(pwd->pw_name);
241 			}
242 		while (i < grmembers)
243 			members[i++] = NULL;
244 		grp->gr_mem = members;
245 	}
246 
247 	if (conf.dryrun)
248 		return print_group(grp);
249 
250 	if (mode == M_ADD && (rc = addgrent(grp)) != 0) {
251 		if (rc == -1)
252 			errx(EX_IOERR, "group '%s' already exists",
253 			    grp->gr_name);
254 		else
255 			err(EX_IOERR, "group update");
256 	} else if (mode == M_UPDATE && (rc = chggrent(name, grp)) != 0) {
257 		if (rc == -1)
258 			errx(EX_IOERR, "group '%s' not available (NIS?)",
259 			    grp->gr_name);
260 		else
261 			err(EX_IOERR, "group update");
262 	}
263 
264 	if (conf.newname != NULL)
265 		name = conf.newname;
266 	/* grp may have been invalidated */
267 	if ((grp = GETGRNAM(name)) == NULL)
268 		errx(EX_SOFTWARE, "group disappeared during update");
269 
270 	pw_log(cnf, mode, W_GROUP, "%s(%u)", grp->gr_name, grp->gr_gid);
271 
272 	free(members);
273 
274 	return EXIT_SUCCESS;
275 }
276 
277 
278 /*
279  * Lookup a passwd entry using a name or UID.
280  */
281 static struct passwd *
282 lookup_pwent(const char *user)
283 {
284 	struct passwd *pwd;
285 
286 	if ((pwd = GETPWNAM(user)) == NULL &&
287 	    (!isdigit((unsigned char)*user) ||
288 	    (pwd = getpwuid((uid_t) atoi(user))) == NULL))
289 		errx(EX_NOUSER, "user `%s' does not exist", user);
290 
291 	return (pwd);
292 }
293 
294 
295 /*
296  * Delete requested members from a group.
297  */
298 static void
299 delete_members(char ***members, int *grmembers, int *i, struct carg *arg,
300     struct group *grp)
301 {
302 	bool matchFound;
303 	char *user;
304 	char *valueCopy;
305 	char *valuePtr;
306 	int k;
307 	struct passwd *pwd;
308 
309 	if (grp->gr_mem == NULL)
310 		return;
311 
312 	k = 0;
313 	while (grp->gr_mem[k] != NULL) {
314 		matchFound = false;
315 		if ((valueCopy = strdup(arg->val)) == NULL)
316 			errx(EX_UNAVAILABLE, "out of memory");
317 		valuePtr = valueCopy;
318 		while ((user = strsep(&valuePtr, ", \t")) != NULL) {
319 			pwd = lookup_pwent(user);
320 			if (strcmp(grp->gr_mem[k], pwd->pw_name) == 0) {
321 				matchFound = true;
322 				break;
323 			}
324 		}
325 		free(valueCopy);
326 
327 		if (!matchFound &&
328 		    extendarray(members, grmembers, *i + 2) != -1)
329 			(*members)[(*i)++] = grp->gr_mem[k];
330 
331 		k++;
332 	}
333 
334 	return;
335 }
336 
337 
338 static          gid_t
339 gr_gidpolicy(struct userconf * cnf, long id)
340 {
341 	struct group   *grp;
342 	gid_t           gid = (gid_t) - 1;
343 
344 	/*
345 	 * Check the given gid, if any
346 	 */
347 	if (id > 0) {
348 		gid = (gid_t) id;
349 
350 		if ((grp = GETGRGID(gid)) != NULL && conf.checkduplicate)
351 			errx(EX_DATAERR, "gid `%u' has already been allocated", grp->gr_gid);
352 	} else {
353 		struct bitmap   bm;
354 
355 		/*
356 		 * We need to allocate the next available gid under one of
357 		 * two policies a) Grab the first unused gid b) Grab the
358 		 * highest possible unused gid
359 		 */
360 		if (cnf->min_gid >= cnf->max_gid) {	/* Sanity claus^H^H^H^Hheck */
361 			cnf->min_gid = 1000;
362 			cnf->max_gid = 32000;
363 		}
364 		bm = bm_alloc(cnf->max_gid - cnf->min_gid + 1);
365 
366 		/*
367 		 * Now, let's fill the bitmap from the password file
368 		 */
369 		SETGRENT();
370 		while ((grp = GETGRENT()) != NULL)
371 			if ((gid_t)grp->gr_gid >= (gid_t)cnf->min_gid &&
372                             (gid_t)grp->gr_gid <= (gid_t)cnf->max_gid)
373 				bm_setbit(&bm, grp->gr_gid - cnf->min_gid);
374 		ENDGRENT();
375 
376 		/*
377 		 * Then apply the policy, with fallback to reuse if necessary
378 		 */
379 		if (cnf->reuse_gids)
380 			gid = (gid_t) (bm_firstunset(&bm) + cnf->min_gid);
381 		else {
382 			gid = (gid_t) (bm_lastset(&bm) + 1);
383 			if (!bm_isset(&bm, gid))
384 				gid += cnf->min_gid;
385 			else
386 				gid = (gid_t) (bm_firstunset(&bm) + cnf->min_gid);
387 		}
388 
389 		/*
390 		 * Another sanity check
391 		 */
392 		if (gid < cnf->min_gid || gid > cnf->max_gid)
393 			errx(EX_SOFTWARE, "unable to allocate a new gid - range fully used");
394 		bm_dealloc(&bm);
395 	}
396 	return gid;
397 }
398 
399 
400 static int
401 print_group(struct group * grp)
402 {
403 	if (!conf.pretty) {
404 		char           *buf = NULL;
405 
406 		buf = gr_make(grp);
407 		printf("%s\n", buf);
408 		free(buf);
409 	} else {
410 		int             i;
411 
412 		printf("Group Name: %-15s   #%lu\n"
413 		       "   Members: ",
414 		       grp->gr_name, (long) grp->gr_gid);
415 		if (grp->gr_mem != NULL) {
416 			for (i = 0; grp->gr_mem[i]; i++)
417 				printf("%s%s", i ? "," : "", grp->gr_mem[i]);
418 		}
419 		fputs("\n\n", stdout);
420 	}
421 	return EXIT_SUCCESS;
422 }
423